// YWROBOT
// Compatible with the Arduino IDE 1.0
// Library version:1.1
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,20,4);
// set the LCD address to 0x27 for a 16 chars and 2 line display

float cm_gauche,cm_droite;
float ratio;

long readUltrasonicDistance(int triggerPin, int echoPin)
{
	pinMode(triggerPin, OUTPUT);  // Clear the trigger
	digitalWrite(triggerPin, LOW);
	delayMicroseconds(2);
	// Sets the trigger pin to HIGH state for 10 microseconds
	digitalWrite(triggerPin, HIGH);
	delayMicroseconds(10);
	digitalWrite(triggerPin, LOW);
	pinMode(echoPin, INPUT);
	// Reads the echo pin, and returns
	// the sound wave travel time in microseconds
	return pulseIn(echoPin, HIGH);
}

void setup()
{
  Serial.begin(9600);
  lcd.init();	// initialize the lcd
  // Print a message to the LCD.
  lcd.backlight();
  lcd.print("--> Distance <--");
	delay(1000);
	lcd.clear();


}

void loop()
{
	ratio = 9.0/400;
	cm_gauche = 0.0342/2 * readUltrasonicDistance(5, 4);
  cm_droite = 0.0342/2 * readUltrasonicDistance(3, 2);

	int croix_gauche = cm_gauche*ratio;
	int croix_droite = cm_droite*ratio;

	// Gauche
	lcd.setCursor(0,0);
	lcd.print(cm_gauche, 0);


	for (int i=0;i<=croix_gauche;i++)
	{
		lcd.setCursor(7+i,0);
		lcd.print("x");
	}
	for (int i=0;i<=croix_droite;i++)
	{
		lcd.setCursor(7+i,1);
		lcd.print("x");
	}


	// Droite
	lcd.setCursor(0,1);
	lcd.print(cm_droite, 0);

	lcd.setCursor(4,0);
	lcd.print("cm");
	lcd.setCursor(4,1);
	lcd.print("cm");

	delay(500);
	lcd.clear();
}